Local structure of hydrated nanocrystalline films of the proton conductor BaZr1-xScxO3-x/2 studied by infrared spectroscopy
Journal article, 2024

We report results from a study of the local structure of hydrated nanocrystalline 2 μm films of the well known proton conductor BaZr1-xScxO3-x/2 with x = 0.45, 0.54 and 0.64, using infrared (IR) spectroscopy. The films were prepared by magnetron sputtering. Analysis of the IR spectra focused on the O–H stretching region (2000—3700 cm-1), which reveals the presence of several distinct O–H stretching bands for which the intensity and frequency of each band vary in an unsystematic manner with Sc concentration. The spectra for the two higher Sc concentrations, x = 0.54 and 0.64, exhibit a distinct, highly intense O–H stretching band centered at around 3400–3500 cm-1, which is assigned to relatively symmetric, weakly hydrogen-bonding, proton configurations. The spectrum for the lower Sc concentration, x = 0.45, does not feature such a band but a broader, weaker, O–H stretching band between approximately 2500 and 3700 cm-1, suggesting that the protons are more homogeneously distributed over a range of different local proton coordinations in this relatively weakly doped material. A comparison to the IR spectra of powder samples of similar compositions suggests that for x = 0.45, the spectra and proton coordination of films and powder samples are similar, whereas for x = 0.54 and 0.64, a larger fraction of protons seems to be located in weakly hydrogen-bonding proton configurations in the films compared to the respective powder samples.

Infrared spectroscopy

Films

Fuel cell

O-H stretch vibration

Proton conducting oxide

Author

Elena Naumovska

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Gabriel Kofi Nzulu

Linköping University

Laura Mazzei

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Arnaud le Febvrier

Linköping University

Kristina Komander

Uppsala University

Martin Magnuson

Linköping University

Max Wolff

Uppsala University

Per Eklund

Linköping University

Maths Karlsson

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Vibrational Spectroscopy

0924-2031 (ISSN)

Vol. 130 103622

Time-resolved spectroscopy of proton and hydride-ion conducting perovskites

Swedish Energy Agency (48712-1), 2020-01-01 -- 2024-12-31.

Subject Categories

Chemical Sciences

Areas of Advance

Materials Science

DOI

10.1016/j.vibspec.2023.103622

More information

Latest update

7/9/2024 3